9 V NiCd or NiMH accumulator charger

Most universal chargers to charge the battery 9 V (8.4 V more). However, while the charging of NiCd or NiMH rechargeable governed by a special circuit or a microprocessor, 9 V batteries are recharged mostly from current sources. I use several of these batteries in measuring instruments, and several have already happened to me, that I forgot the battery and it nabíjel few days. Described charger charges while also just a constant current charging but after about 14 hours ends.

Charging current / charge current : 15 mA (can be changed / CAN BE CHANGED ).
Charging / Charging time : about / approx. 13.5 hours (can be changed / CAN BE CHANGED )
Voltage / Supply Voltage : 15-25 V dc or 12-20 V AC.
15 to 25 VDC or 12 to 20 VAC
Charge indication / Charge Indication : red / red LED.
Charging discontinuation LED1, LED2 blink timer and oscillator work (Blink approx. 40 times per minute for 13.5 hours.)
Connecting the charger is in the picture 1 . The battery is charged by current source transistor T1 and T2. LED1 indicates charging. Because the charging current is usually 10 to 20 mA LEDs can be connected directly in series with battery. Charging timer circuit controls the 4541st It's actually a complete RC oscillator and binary divider several auxiliary circuits. They allow you to set the automatic resetting divider for voltage drop (and hence the power) and blocked after the first divider output pulse (one shot mode). Both these functions are used by setting pin 5 (auto reset) and 10 (modem). Timing is controlled oscillator RC , which has a resistor R6 and capacitor C2 set the frequency 0.7 Hz. Capacitor C3 prevents parasites kmit?m oscillator and its small capacity has a negligible effect on the frequency of the oscillator. Vibration of the oscillator indicates LED2. Divider is pin 12 and 13 (A0 and A1) set the dividing ratio of 2 16 , ie 65536th The output (pin 8) is the log level. ¥ 1 half of...